Orbeon stops responding when the /new page for a form is accessed from both Form Runner and the Proxy Portlet

Environment:

Tomcat 7
Orbeon 4.9
Proxy Portlet 4.9
Liferay 6.2 CE GA2.

Steps to reproduce:

1. Add the Proxy Portlet to a page
2. Configure it to point to the /new page for a form (I'm using URL parameters)
3. Open the /new page in the Proxy Portlet (works fine)
4. Open the /new page for the same form in Form Runner (doesn't respond)

(Note that it has to be the same form. Going to the /edit page for a different document ID is fine, but editing the same document in Proxy Portlet and Form Runner causes the same issue.)

At this point, the orbeon.log indicates that it has received the request, but it never responds. No further log messages are output. Any further requests to Orbeon get no response. Orbeon just logs that the request is received and seems to do nothing. No CPU is used.

The Tomcat "Server Status" page indicates that the request to /new in Form Runner is stuck. See output below:

Stage Time  B Sent  B Recv  Client (Forwarded)  Client (Actual) VHost Request
R ? ? ? ? ? ?
P ? ? ? ? ? ?
S 58607 ms  0 KB  0 KB  10.10.10.37 10.10.10.37 myserver.mydomain.com GET /orbeon/fr/nrs_smart_forms/project/new HTTP/1.1
R ? ? ? ? ? ?
S 58581 ms  0 KB  0 KB  127.0.0.1 127.0.0.1 localhost GET /orbeon/fr/service/persistence/crud/nrs_smart_forms/project/form/form.xhtml HTTP/1.1
P ? ? ? ? ? ?
P ? ? ? ? ? ?
S 10 ms 0 KB  0 KB  10.10.10.58 10.10.10.58 myserver.mydomain.com GET /manager/status?org.apache.catalina.filters.CSRF_NONCE=A5E8D7B1440E2CA4E6CBF9A5ABA10535 HTTP/1.1
P ? ? ? ? ? ?
R ? ? ? ? ? ?
P ? ? ? ? ? ?
P: Parse and prepare request S: Service F: Finishing R: Ready K: Keepalive

I attached my orbeon.log. I enabled dev mode in the hope that it would provide more information, but nothing stands out.

It looks like the only workaround I have for this is to use separate instances of Orbeon for Proxy Portlet and Form Runner/Builder.

I forgot to note that it doesn't matter which is accessed first, Proxy Portlet or Form Runner. The first one accessed will work and the second will get no response.

The workaround of running two instances of Orbeon is working. There doesn't appear to be an issue with running two instances in the same container with different context roots.

I added this bug to [issue #2117 on github](https://github.com/orbeon/orbeon-forms/issues/2117) and referenced this discussion thread.

I have no doubt this is happening, but I don't reproduce it immediately.

- direct side: /fr/orbeon/controls/new
- proxy portlet: orbeon / control / New Page

Do you have the same problem when using the orbeon/controls form?

-Erik